Overview

• The SickKids team reported the findings at the European Respiratory Society Congress in Amsterdam.
• Analysis of 1,050 children measured dog (Can f1), cat (Fel d1) and bacterial endotoxin levels in household dust collected at 3–4 months of age.
• At five years, higher Can f1 exposure was associated with 48% lower odds of physician-diagnosed asthma and with improved lung function (FEV1).
• The protective association persisted across genetic-risk strata, while cat allergen and endotoxin showed no similar link.
• The study is observational, and investigators point to possible microbiome or immune mechanisms that require confirmation in further studies.